Hydraulic self-adaptive adjusting foot

ABSTRACT

The invention discloses a hydraulic self-adaptive adjusting foot wherein an upper cover is arranged at the upper end of the bottom shell, a piston body arranged in the bottom shell and a piston ring seal arranged between outer circumferential face of piston body and inner wall of bottom shell; a return spring is arranged between bottom of the piston body and the bottom shell while the bottom end of the support post penetrates into the bottom shell from the center hole of the upper cover in a sealing mode. A groove is provided in the center of bottom surface of the flange at bottom end of said support post and a steel ball return spring is set in said groove; in the middle of bottom surface of piston body is provided with spring groove in which sets the top end of return spring; at the axis of spring groove sets the hydraulic oil passage between top end of which and bottom end of steel ball return spring arranges the steel ball. The invention has following merits: the hydraulic oil flows and migrates in upper and lower piston chambers via hydraulic oil passage controlled by steel ball joint work of which and return spring enables supporting objects reach stable state and bottom foot&#39;s height be automatically adjusted; the appearance of invention is simple and compact, suitable for repeating adjustments.

TECHICAL FIELD

The invention relates to a hydraulic self-adaptive adjusting foot employed in parts of bases or legs of furniture like tables and chairs that touches ground to realize purpose of supporting and stabilizing tables, chairs, and stools; when the ground is not very flat, the table can be stabilized by virtue of compression from the weight of objects that the hydraulic self-adaptive adjusting foot supports (table, chair, workbench, etc.).

BACKGROUND OF THE INVENTION

In the using process of tables, chairs, and other furniture, especially usage of tables for commercial purposes, adjustable foot will be mounted sometimes at the bottom of such furniture so as to provide a stable using environment for customers; most adjusting feet in the market are in the form of screws which adjust height via screwing of screws to achieve stabilization of tables, which is relatively troublesome and arduous as the screw has to be rotated by artificial driven or usage of tools.

SUMMARY OF THE INVENTION

The invention aims to provide a hydraulic self-adaptive adjusting foot to solve bothering problem of adjusting height via hand regulation or tools existing in current technology.

To achieve above purpose, the invention adopts following technical plan: a hydraulic self-adaptive adjusting foot comprises a bottom shell, an upper cover, a support post, a return spring, a piston body and a piston ring seal wherein the upper cover is arranged at the upper end of the bottom shell, the piston body arranged in the bottom shell and a piston ring seal arranged between outer circumferential face of piston body and inner wall of bottom shell; a return spring is arranged between bottom of the piston body and the bottom shell while the bottom end of the support post penetrates slidably into the bottom shell from the center hole of the upper cover in a sealing mode; the invention is characterized in that a flange is arranged at the bottom of said support post and in the center of bottom surface of said flange is provided with a groove in which a steel ball return spring is provided; in the middle of bottom surface of piston body is provided with spring groove in which sets the top end of return spring; at the axis of spring groove sets the through hole as hydraulic oil passage between top end of which and bottom end of steel ball return spring arranges the steel ball.

An upper flange for mounting the bottom end of the return spring is arranged at the center of the bottom surface inside said bottom shell.

Said upper cover is connected with the upper end of the bottom shell through threads.

The steel ball return spring is a tower-shaped spring whose diameter of the small-diameter end is slightly shorter than that of said steel ball and abuts against the steel ball.

A chamfer matched with the spherical surface of the steel ball is arranged at the top end of the hydraulic oil passage.

The invention has following advantage: by utilizing the fluidity and pressure conduction principle of hydraulic oil, the hydraulic oil migrates in upper and lower piston chamber joint work of which and return force of return spring enables supporting objects reach stable state and bottom foot's height be automatically adjusted; the appearance of invention is simple and compact, suitable for repeating adjustments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. is an axial section view illustrating the overall structure of the invention;

FIG. 2. is an exploded perspective view of the invention.

Description of reference numerals: 1. piston ring seal; 2. support post; 21. flange at the bottom end of the support post; 3. seal sleeve of upper cover; 4. upper cover; 5. steel ball return spring; 6. steel ball; 7. piston body; 71. hydraulic oil passage; 8. bottom shell; 9. return spring; 10. sealing ring of support post.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG.1 and FIG. 2, the invention discloses a hydraulic self-adaptive adjusting foot comprising a bottom shell 8, an upper cover 4, a support post 2, a return spring 9, a piston body 7 and a piston ring seal 1 wherein the upper cover 4 is arranged at the upper end of the bottom shell 8, the piston body 7 arranged in the bottom shell and the piston ring seal 1 arranged between outer circumferential face of piston body 7 and inner wall of bottom shell 8; a return spring 9 is arranged between bottom of the piston body 7 and the bottom shell 8 while the bottom end of the support post 2 penetrates slidably into the bottom shell 8 from the center hole of the upper cover 4 in a sealing mode. The invention is characterized in that a flange 21 is arranged at the bottom end of said support post 2 and in the center of bottom surface of said flange 21 is provided with a groove in which a steel ball return spring 5 is provided; in the middle of bottom surface of piston body 7 is provided with spring groove in which sets the top end of return spring 9; at the axis of spring groove sets the through hole as hydraulic oil passage 71 between top end of which and bottom end of steel ball return spring 5 arranges the steel ball 6; between said support post 2 and the center hole of the upper cover 4 arranges seal sleeve of upper cover 3; at the inner circumferential surface of said seal sleeve of upper cover 3 is provided with at least one annular groove in which the sealing ring of support post is arranged.

An upper flange for mounting the bottom end of the return spring 9 is arranged at the center of the bottom surface inside said bottom shell 8.

Said upper cover 4 is connected with the upper end of the bottom shell 8 through threads.

Said steel ball return spring 5 is a tower-shaped spring whose diameter of the small-diameter end is slightly shorter than that of said steel ball 6 and abuts against the steel ball 6.

A chamfer matched with the spherical surface of the steel ball 6 is arranged at the top end of the hydraulic oil passage 71.

In the using process, the top end of support post 2 connected with its supporting objects, the invention features in adjusting foot's height automatically through hydraulic principle. To open or close hydraulic oil passage 71 in the middle of piston body 7 is controlled by a steel ball 6; when the bottom foot is subject to downward pressure, the piston moves downward and hydraulic oil in lower piston chamber flows to upper piston chamber through oil passage; then the steel ball 6 is lifted by upward pressure from the hydraulic oil and hydraulic oil passage 71 opens. When the downward force of piston and elastic force of return spring 9 reach a balance, the piston stops moving and steel ball 6 is reset under effect of steel ball return spring. Thus the bottom foot reach new stable state and its height is automatically adjusted. When upper force is withdrawn(supporting object is lifted), the piston moves upward under effect of return spring 9 and steel ball 6 closes the oil passage, the hydraulic oil at the upper piston flows to the bottom through periphery of the piston ring seal 1, thus the pressure of adjusting foot is released and the piston is reset. 

1. A hydraulic self-adaptive adjusting foot comprises a bottom shell, an upper cover, a support post, a return spring, a piston body and a piston ring seal wherein the upper cover is arranged at the upper end of the bottom shell with openings, the piston body arranged in the bottom shell and a piston ring seal arranged between outer circumferential face of piston body and inner wall of bottom shell; a return spring is arranged between bottom of the piston body and the bottom shell while the bottom end of the support post penetrates slidably into the bottom shell from the center hole of the upper cover in a sealing mode; the invention is characterized in that a flange is arranged at the bottom of said support post and in the center of bottom surface of said flange is provided with a groove in which a steel ball return spring is provided; in the middle of bottom surface of piston body is provided with spring groove in which sets the top end of return spring; at the axis of spring groove sets the through hole as hydraulic oil passage between top end of which and bottom end of steel ball return spring arranges the steel ball.
 2. The hydraulic self-adaptive adjusting foot according to claim 1 wherein an upper flange for mounting the bottom end of the return spring is arranged at the center of the bottom surface inside said bottom shell.
 3. The hydraulic self-adaptive adjusting foot according to claim 1 wherein said upper cover is connected with the upper end of the bottom shell through threads.
 4. The hydraulic self-adaptive adjusting foot according to claim 1 wherein the steel ball return spring is a tower-shaped spring whose diameter of the small-diameter end is slightly shorter than that of said steel ball and abuts against the steel ball.
 5. The hydraulic self-adaptive adjusting foot according to claim 1 wherein a chamfer matched with the spherical surface of the steel ball is arranged at the top end of the hydraulic oil passage.
 6. The hydraulic self-adaptive adjusting foot according to claim 1 wherein between said support post 2 and the center hole of the upper cover 4 arranges seal sleeve of upper cover 3; at the inner circumferential surface of said seal sleeve of upper cover 3 is provided with at least one annular groove in which the sealing ring of support post is arranged. 